1. Field of the Invention
The present invention relates to an electronic device including a printed circuit board, a connector mounted on the printed circuit board, and a casing housing the printed circuit board therein.
2. Description of the Related Art
In a conventional electronic device, a printed circuit board is housed in a case having an opening portion, and a housing of a connector mounted on the printed circuit board covers the opening portion of the case.
For example, in an electronic control device disclosed in JP-A-2005-160207, a case has an approximately rectangular box shape and has an opening portion at one sidewall. Each of two sidewalls located on opposite sides of the one sidewall has a fixing hole. A connector has two fixing projections each engaging with corresponding one of the fixing holes. Thereby, a unit body including the connector is fixed to the case. Furthermore, the one sidewall having the opening portion has engaging ribs protruding to an outside of the case and the connector has engaging grooves. Each of the engaging ribs is lifted into corresponding one of the engaging grooves. Thereby, the two sidewalls are restricted from opening toward the outside of the case. As a result, the engagements of the fixing holes and the fixing projections are restricted from being released.
In the present electronic device, center portions of the two sidewalls in a longitudinal direction of the two sidewalls may warp toward the outside of the case due to a change in a temperature. The engaging ribs and the engaging projections are difficult to restrict the warps of the two sidewalls. Thus, the engagements of the fixing holes and the fixing projections are possibly released.
In an electronic device disclosed in Japanese Patent No. 3,769,460, a case has an approximately rectangular box shape and one side of the case opens to provide an opening portion. The case has first fixing parts (holes) adjacent to the opening portion. A housing of a connector has second fixing parts (projections) adjacent to the opening portion. The opening portion is covered with the housing in a state where each of the second fixing parts engages with corresponding one of the first engaging parts. The opening portion is deformed to have an arcuate shape before the housing is inserted therein. By inserting the housing into the opening portion, the shape of the opening portion is adjusted so as to strengthen the engagements of the first fixing parts and the second fixing parts.
In the present electronic device, the shape of the opening portion may be deformed and/or sidewalls may warp due to a change in the temperature. Thus, the engagements of the first engaging parts and the second engaging parts are possibly released due to the deformation of the opening portion or the warps of the sidewalls.